OTR520D:
①. Base: CAT 329D(HHP)
②. Max pile diameter (mm): 1800
③. Max pile depth (m): 60
④. Engine: CAT C7 ACERT 187KW
⑤. Maximum nominal torque (kNm): 200
⑥. Undercarriage with expandable (mm): 3000-4300
……More info  

1. Adopts the complete OEM Caterpillar retractable-crawler dedicated chasis，Its telescopic scope between the two crawler ends extends from 3000mm(at transportation) to 4400mm(at work). Undercarriage with expandable and removable tracks by means of hydraulic cylinders, guarantee exception stabbility in any type of ground. It has considerable traction force which allows easy movement even in the most difficult job sites.
2.Takes international top CAT Diesel engine with electric injection, turbocharged and air inter-cooling system. It is high reliability, fuel economy and power reserves. Emissions meet standard EPAC-Ⅲ.
3.The winches are positioned in the lower part of the mast, in front of the cabin, so that the operator can constantly check the proper operation. Thanks to the fact that the cable moves parallely to the mast, flection is not created on the upper part of the mast and operating life of the cable is therefore much longer. Tail positioned winch is available for heavy-duty type.
4.New design parallelogram system, computer optimized design and simplified pin connection system featured with nice appearance, great driving force and good stability, especially shaped to fit crowd system, allowing working radius adjustment always maintaining the mast in vertical position. The parallelogram system is easily for convenient transform between transportation and working conditions.
5.Self-erecting mast, high level anti-shock technology and high-strenth material steel attribute to that max torque can be applied all over the mast length. Multipurpose design for cylinder crowed system. Sensor and control center realize real-time measurement of the inclination angle, auto adjustment of mast verticality and inching adjustment.
6.Crowd system by means of long stroke hydraulic cylinder or crowd winch separately, are option for your exact request.
7.Rotary head with variable displacement motors and one high spin off speed. And rotary is extremely reliable, it has been disgned in order to gurantee a very compact, efficient and powerful rotary. The transmission group of rotary is made up of a hydraulic motor and new power shift purposely studied and designed to obtain maximum perfomance. During the drilling phase, the rotary has the entire power of the diesel at its complete disposal. Adapter of rotary is essential to absorb the considerable shock connected to the high speed of the main winch.
8.Telescopic kelly bar with guide made by high quality specially for high boring strength and torque force. Available with friction or inter-locking type.
9. All the main hydraulic components(pumps, valve, motor, connector) are from well-known international brands such as Bosch-Rexroth, brevini, which ensure the stability, reliability, high-efficiency and energy-saving of the entire system
10.Electronic controlling system is an innovative system, developed by Osaint, which controls and monitors the operation of the machines. For ease of operation, the system is controlled by a touch screen located in the cab. The system function is to enable the machines to perform different functions more efficiently. A dedicated power module electronic control and CAN-Bus system ensures the main pumps and Disel engine to work at their most effective and productive stages.